BACKGROUND OF THE INVENTION
Field of the Invention
[0001] The present invention relates in general to mobile communication terminals, and more
particularly to a method for branching data in a mobile communication terminal.
Description of the Prior Art
[0002] Until now, a conventional mobile communication system has provided only a pure speech
service or a simple short message service (referred to hereinafter as SMS). With a
third-generation mobile communication system being developed, there have recently
been proposed a multimedia service and short/long packet services.
[0003] Such third-generation services require a new layer, which is called a media access
control (referred to hereinafter as MAC) sublayer.
[0004] The MAC sublayer has to perform a branching operation suitable to a service characteristic
in order to appropriately process a variety of services.
[0005] However, the conventional mobile communication system is disadvantageous in that
the MAC sublayer cannot efficiently branch various multimedia and packet services
because the system provides only simple services such as the SMS.
SUMMARY OF THE INVENTION
[0006] Therefore, the present invention has been made in view of the above problem, and
it is an object of the present invention to provide a method for branching data in
a mobile communication terminal, in which a media access control sublayer attaches
logical channel types based on traffic characteristic identifiers from a radio resource
control layer and other upper layers to a media access control header and performs
mapping and multiplexing/demultiplexing between logical channels and transport channels
according to the attached logical channel types to branch the data.
[0007] In accordance with one aspect of the present invention, in a method for performing
data communication between a mobile station and a network which have media access
control sublayers, respectively, there is provided a method for branching data in
a mobile communication terminal, comprising the first step of allowing each of the
media access control sublayers of the mobile station and network to attach logical
channel types based on traffic characteristic information and a radio bearer status
to a media access control header contained in data to be sent, in a data sending mode;
the second step of allowing each of the media access control sublayers to branch the
data to be sent, to transport channels corresponding to the attached logical channel
types; the third step of allowing each of the media access control sublayers to determine
logical channels corresponding to logical channel types of a media access control
header contained in received data in a data receiving mode; and the fourth step of
allowing each of the media access control sublayers to branch the received data to
the determined logical channels.
[0008] Preferably, each of the second and fourth steps may include the step of allowing
each of the media access control sublayers to perform a channel mapping operation
in a one-to-one manner, a channel multiplexing operation in a many-to-one manner and
a channel demultiplexing operation in a one-to-many manner to branch the data to be
sent or the received data.
[0009] Further, preferably, the traffic characteristic information may include traffic characteristic
identifiers transferred from a radio resource control layer and other upper layers.
[0010] Further, preferably, each of the traffic characteristic identifiers may represent
any one of random access data, synchronization data, system information, paging information,
forward access grant information, short message service data, no radio bearer-type
short packet data, signaling data, radio bearer-type short/long packet data, multicast
signaling data, multicast data and speech characteristics.
[0011] In accordance with another aspect of the present invention, in a method for performing
data communication between a mobile station and a network which have media access
control sublayers, respectively, there is provided a method for branching data in
a mobile communication terminal, comprising the first step of allowing each of said
media access control sublayers of said mobile station and network to set information
regarding connection between logical channels and transport channels on the basis
of traffic characteristic information and a radio bearer status; the second step of
allowing each of said media access control sublayers to attach logical channel types
based on the set connection information to a media access control header contained
in data to be sent, in a data sending mode; and the third step of allowing each of
said media access control sublayers to branch said data to be sent, to transport channels
corresponding to the attached logical channel types.
[0012] In a feature of the present invention, a media access control sublayer attaches logical
channel types based on traffic characteristic identifiers from a radio resource control
layer and other upper layers to a media access control header and performs mapping
and multiplexing/demultiplexing between logical channels and transport channels according
to the attached logical channel types to branch data. This makes it possible to efficiently
provide various multimedia and packet services.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The above and other objects, features and advantages of the present invention will
be more clearly understood from the following detailed description taken in conjunction
with the accompanying drawings, in which:
Figs. 1a and 1b are views illustrating data branched states between mobile and base
stations to which a method for branching data in a mobile communication terminal in
accordance with the present invention is applied.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0014] Figs. 1a and 1b are views illustrating data branched states between mobile and base
stations to which a method for branching data in a mobile communication terminal in
accordance with the present invention is applied.
[0015] A method for branching data in a mobile communication terminal in accordance with
the present invention will hereinafter be described in detail with reference to Figs.
1a and 1b.
[0016] As shown in Figs. 1a and 1b, channels associated with a MAC sublayer are classified
into logical channels and transport channels.
[0017] The logical channels are mapped into MAC-service access points (referred to hereinafter
as SAPs) in interfaces between the MAC sublayer and upper layers, respectively.
[0018] The above logical channels may generally be classified into a synchronization control
channel (referred to hereinafter as SCCH) for transferring system synchronization
data in simplex through a downlink, a broadcast control channel (referred to hereinafter
as BCCH) for broadcasting system information in simplex through the downlink, a paging
control channel (referred to hereinafter as PCCH) for transferring paging information
in simplex through the downlink, a common control channel (referred to hereinafter
as CCCH) for transferring random access data, forward access control data and short
packet data in duplex through the downlink and an uplink, a dedicated control channel
(referred to hereinafter as DCCH) for transferring dedicated signal control information
in duplex through the downlink and uplink, and a dedicated traffic channel (referred
to hereinafter as DTCH) for transferring dedicated user long/short packet data in
duplex through the downlink and uplink.
[0019] The CCCH, DCCH and DTCH are adapted to transfer some data on the basis of the connection
between the MAC sublayer and a radio resource control (referred to hereinafter as
RRC) layer and the presence of a radio bearer. Namely, the CCCH transfers random access
data under the condition that the RRC layer is not connected to the MAC sublayer,
and the DCCH transfers SMS data, signaling data and a multicast signal under the condition
that the RRC layer is connected to the MAC sublayer. The DTCH transfers short/multicast
packet data under the condition that no radio bearer is present and short/long/multicast
packet data under the condition than a radio bearer is present.
[0020] The above multicast signal, short/multicast packet data and short/long/multicast
packet data are available only on a network.
[0021] The transport channels are mapped into physical (referred to hereinafter as PHY)-SAPs
in interfaces between the MAC sublayer and PHY layers, respectively.
[0022] The above transport channels may generally be classified into a synchronization channel
(referred to hereinafter as SCH) including first and second channels for transferring
a system synchronization signal, a broadcast channel (referred to hereinafter as BCH)
for broadcasting system information in simplex through the downlink, a paging channel
(referred to hereinafter as PCH) for transferring paging information in simplex through
the downlink, a forward access channel (referred to hereinafter as FACH) for transferring
forward access grant information and short packet data in simplex through the downlink,
a random access channel (referred to hereinafter as RACH) for transferring random
access data and short packet data in simplex through the uplink, a downlink shared
channel (referred to hereinafter as DSCH) for multicasting user data in simplex through
the downlink, and a dedicated channel (referred to hereinafter as DCH) for transferring
dedicated signal information and dedicated user data in duplex through the downlink
and uplink.
[0023] On the other hand, in a sending entity, the MAC sublayer has to create a MAC protocol
data unit (PDU) with a MAC header including a type of a logical channel through which
upper layer data is to be transferred. In a receiving entity, the MAC sublayer utilizes
the logical channel type of the MAC header to determine a logical channel into which
the received MAC PDU is to be demultiplexed. This procedure will hereinafter be described
in detail while being classified into channel mapping and channel multiplexing/demultiplexing
between a mobile station and a network.
[0024] First, a description will be given of a channel mapping operation for data sending
and reception between the mobile station and network.
[0025] The channel mapping operation is performed in the mobile station in the following
manner.
[0026] In the case where the mobile station is to send data to the network, the MAC sublayer
of the mobile station maps the CCCH which is a logical channel for transferring random
access data, to the RACH which is a transport channel, in a one-to-one manner.
[0027] In the case where the mobile station is to receive data from the network, the MAC
sublayer of the mobile station maps the SCH which is a transport channel for transferring
signaling data, the BCH which is a transport channel for transferring system information
and the PCH which is a transport channel for transferring paging information, respectively,
to the SCCH, BCCH and PCCH which are logical channels, in the one-to-one manner.
[0028] The channel mapping operation is performed in the network in the following manner.
[0029] In the case where the network is to send data to the mobile station, the MAC sublayer
of the network maps the SCCH which is a logical channel for transferring system synchronization
data, the BCCH which is a logical channel for transferring system information, the
PCCH which is a logical channel for transferring paging information and the CCCH which
is a logical channel for transferring forward access grant information, respectively,
to the SCH, BCH, PCH and FACH which are transport channels, in the one-to-one manner.
[0030] Noticeably, the channel mapping operation is not performed in the network with respect
to data which is sent from the mobile station to the network.
[0031] Next, a description will be given of channel multiplexing/demultiplexing operations
of the mobile station.
[0032] The channel multiplexing operation of the mobile station is performed in the following
manner.
[0033] First, the RRC layer and other upper layers of the mobile station transfer traffic
characteristic identifiers to the MAC sublayer of the mobile station.
[0034] The MAC sublayer of the mobile station attaches logical channel types based on traffic
characteristics of the traffic characteristic identifiers from the RRC layer and other
upper layers to a MAC header. Then, the MAC sublayer branches data to transport channels
corresponding to the attached logical channel types through PHY-SAPs.
[0035] The traffic characteristics may generally be random access data, synchronization
data, system information, paging information, forward access grant information, SMS
data, short packet data (no radio bearer), signaling data, short/long packet data
(radio bearer), multicast signaling data, multicast data and speech characteristics.
[0036] For example, if the random access data, SMS data and no radio bearer-type short packet
data characteristics are required, the MAC sublayer of the mobile station attaches
types of the CCCH, DCCH and DTCH to the MAC header and multiplexes the CCCH, DCCH
and DTCH to the RACH in a many-to-one manner to branch data through PHY-SAPs. Here,
the CCCH is a logical channel for transferring random access data, the DCCH is a logical
channel for transferring SMS data, the DTCH is a logical channel for transferring
no radio bearer-type short packet data, and the RACH is a transport channel.
[0037] In the case where the signaling data and radio bearer-type short/long packet data
characteristics are required, the MAC sublayer of the mobile station attaches types
of the DCCH and DTCH to the MAC header and multiplexes the DCCH and DTCH to the DCH
in the many-to-one manner to branch data through PHY-SAPs. Here, the DCCH is a logical
channel for transferring signaling data, the DTCH is a logical channel for transferring
radio bearer-type short/long packet data, and the DCH is a transport channel.
[0038] The channel demultiplexing operation of the mobile station is performed in the following
manner.
[0039] The network, or sending entity, attaches logical channel types based on traffic characteristics
to a MAC header and the mobile station, or receiving entity, performs the channel
demultiplexing operation on the basis of the logical channel types attached to the
MAC header.
[0040] For example, if a transport channel through which data from the network, or sending
entity, is sent is the FACH, the MAC sublayer of the mobile station demultiplexes
the FACH to logical channels corresponding to traffic characteristics of logical channel
types attached to a MAC header of the sent data in a one-to-many manner to branch
the sent data to upper layers through MAC-SAPs.
[0041] That is, for example, in the case where the forward access grant information, SMS
data and no radio bearer-type short packet data characteristics are required by the
sending entity, the MAC sublayer of the mobile station recognizes that logical channel
types attached to a MAC header of received data correspond respectively to the CCCH,
DCCH and DTCH and demultiplexes the FACH to the CCCH, DCCH and DTCH in the one-to-many
manner to branch the received data to upper layers through MAC-SAPs. Here, the FACH
is a transport channel, and the CCCH, DCCH and DTCH are logical channels.
[0042] If the multicast signaling data and multicast data characteristics are required by
the sending entity, the MAC sublayer of the mobile station recognizes that logical
channel types attached to a MAC header of received data correspond respectively to
the DCCH and DTCH and demultiplexes the DSCH to the DCCH and DTCH in the one-to-many
manner to branch the received data to upper layers through MAC-SAPs. Here, the DSCH
is a transport channel, and the DCCH and DTCH are logical channels.
[0043] In the case where the dedicated signaling data and radio bearer-type short/long packet
data characteristics are required by the sending entity, the MAC sublayer of the mobile
station recognizes that logical channel types attached to a MAC header of received
data correspond respectively to the DCCH and DTCH and demultiplexes the DCH to the
DCCH and DTCH in the one-to-many manner to branch the received data to upper layers
through MAC-SAPs. Here, the DCH is a transport channel, and the DCCH and DTCH are
logical channels.
[0044] Finally, a description will be given of channel multiplexing/demultiplexing operations
of the network.
[0045] The channel multiplexing operation of the network is performed in the following manner.
[0046] First, the RRC layer and other upper layers of the network transfer traffic characteristic
identifiers to the MAC sublayer of the network.
[0047] The MAC sublayer of the network attaches logical channel types based on traffic characteristics
of the traffic characteristic identifiers from the RRC layer and other upper layers
to a MAC header. Then, the MAC sublayer branches data to transport channels corresponding
to the attached logical channel types.
[0048] The traffic characteristics may generally be random access data, synchronization
data, system information, paging information, forward access grant information, SMS
data, short packet data (no radio bearer), signaling data, short/long packet data
(radio bearer), multicast signaling data, multicast data and speech characteristics.
[0049] For example, in the case where the forward access grant information, SMS data and
no radio bearer-type short packet data characteristics are required, the MAC sublayer
of the network attaches types of the CCCH, DCCH and DTCH to the MAC header and multiplexes
the CCCH, DCCH and DTCH to the FACH in the many-to-one manner to branch data through
PHY-SAPs. Here, the CCCH is a logical channel for transferring forward access grant
information, the DCCH is a logical channel for transferring SMS data, the DTCH is
a logical channel for transferring no radio bearer-type short packet data, and the
FACH is a transport channel.
[0050] If the multicast signaling data and multicast data characteristics are required,
the MAC sublayer of the network attaches types of the DCCH and DTCH to the MAC header
and multiplexes the DCCH and DTCH to the DSCH in the many-to-one manner to branch
data through PHY-SAPs. Here, the DCCH is a logical channel for transferring multicast
signaling data, the DTCH is a logical channel for transferring multicast data, and
the DSCH is a transport channel.
[0051] In the case where the signaling data and radio bearer-type short/long packet data
characteristics are required, the MAC sublayer of the network attaches types of the
DCCH and DTCH to the MAC header and multiplexes the DCCH and DTCH to the DCH in the
many-to-one manner to branch data through PHY-SAPs. Here, the DCCH is a logical channel
for transferring signaling data, the DTCH is a logical channel for transferring radio
bearer-type short/long packet data, and the DCH is a transport channel.
[0052] The channel demultiplexing operation of the network is performed in the following
manner.
[0053] The mobile station, or sending entity, attaches logical channel types based on traffic
characteristics to a MAC header and the network, or receiving entity, performs the
channel demultiplexing operation on the basis of the logical channel types attached
to the MAC header.
[0054] For example, in the case where a transport channel through which data from the mobile
station, or sending entity, is sent is the RACH, the MAC sublayer of the network demultiplexes
the RACH to logical channels corresponding to traffic characteristics of logical channel
types attached to a MAC header of the sent data in the one-to-many manner to branch
the sent data to upper layers through MAC-SAPs.
[0055] Namely, for example, if the forward access grant information, SMS data and no radio
bearer-type short packet data characteristics are required by the sending entity,
the MAC sublayer of the network recognizes that logical channel types attached to
a MAC header of received data correspond respectively to the CCCH, DCCH and DTCH and
demultiplexes the RACH to the CCCH, DCCH and DTCH in the one-to-many manner to branch
the received data to upper layers through MAC-SAPs. Here, the RACH is a transport
channel, and the CCCH, DCCH and DTCH are logical channels.
[0056] In the case where the dedicated signaling data and radio bearer-type short/long packet
data characteristics are required by the sending entity, the MAC sublayer of the network
recognizes that logical channel types attached to a MAC header of received data correspond
respectively to the DCCH and DTCH and demultiplexes the DCH to the DCCH and DTCH in
the one-to-many manner to branch the received data to upper layers through MAC-SAPs.
Here, the DCH is a transport channel, and the DCCH and DTCH are logical channels.
[0057] As apparent from the above description, according to the present invention, the MAC
sublayer performs mapping and multiplexing/demultiplexing between logical channels
and transport channels according to traffic characteristics to branch data. Therefore,
the present invention has the effect of efficiently providing various multimedia and
packet services.
[0058] Although the preferred embodiments of the present invention have been disclosed for
illustrative purposes, those skilled in the art will appreciate that various modifications,
additions and substitutions are possible, without departing from the scope and spirit
of the invention as disclosed in the accompanying claims.
1. In a method for performing data communication between a mobile station and a network
which have media access control sublayers, respectively, a method for branching data
in a mobile communication terminal, comprising the steps of:
a) allowing each of said media access control sublayers of said mobile station and
network to attach logical channel types based on traffic characteristic information
and a radio bearer status to a media access control header contained in data to be
sent, in a data sending mode;
b) allowing each of said media access control sublayers to branch said data to be
sent, to transport channels corresponding to the attached logical channel types;
c) allowing each of said media access control sublayers to determine logical channels
corresponding to logical channel types of a media access control header contained
in received data in a data receiving mode; and
d) allowing each of said media access control sublayers to branch said received data
to said determined logical channels.
2. A method for branching data in a mobile communication terminal, as set forth in Claim
1, wherein each of said steps b) and d) includes the step of allowing each of said
media access control sublayers to perform a channel mapping operation in a one-to-one
manner, a channel multiplexing operation in a many-to-one manner and a channel demultiplexing
operation in a one-to-many manner to branch said data to be sent or said received
data.
3. A method for branching data in a mobile communication terminal, as set forth in Claim
1, wherein said traffic characteristic information includes traffic characteristic
identifiers transferred from a radio resource control layer and other upper layers.
4. A method for branching data in a mobile communication terminal, as set forth in Claim
3, wherein each of said traffic characteristic identifiers represents any one of random
access data, synchronization data, system information, paging information, forward
access grant information, short message service data, no radio bearer-type short packet
data, signaling data, radio bearer-type short/long packet data, multicast signaling
data, multicast data and speech characteristics.
5. A method for branching data in a mobile communication terminal, as set forth in Claim
1, wherein, in said data sending mode, said media access control sublayer of said
mobile station is adapted to, if said data to be sent is random access data, attach
a type of a common control channel to said media access control header contained in
said data to be sent and map said common control channel to a random access channel
in a one-to-one manner, said common control channel and random access channel being
logical and transport channels for said random access data, respectively.
6. A method for branching data in a mobile communication terminal, as set forth in Claim
1, wherein, in said data receiving mode, said media access control sublayer of said
mobile station is adapted to, if said logical channel types of said media access control
header contained in said received data correspond respectively to a synchronization
control channel, a broadcast control channel and a paging control channel, map a synchronization
channel, a broadcast channel and a paging channel respectively to said synchronization
control channel, broadcast control channel and paging control channel in a one-to-one
manner to branch said received data to said synchronization control channel, broadcast
control channel and paging control channel, said synchronization control channel and
synchronization channel being logical and transport channels for synchronization data,
respectively, said broadcast control channel and broadcast channel being logical and
transport channels for system information, respectively, said paging control channel
and paging channel being logical and transport channels for paging information, respectively.
7. A method for branching data in a mobile communication terminal, as set forth in Claim
1, wherein, in said data sending mode, said media access control sublayer of said
mobile station is adapted to, if said traffic characteristic information includes
synchronization data, system information, pacing information and forward access grant
information characteristics, attach types of a synchronization control channel, broadcast
control channel, paging control channel and common control channel to said media access
control header contained in said data to be sent and map said synchronization control
channel, broadcast control channel, paging control channel and common control channel
respectively to associated transport channels in a one-to-one manner to branch said
data to be sent, to the associated transport channels, said synchronization control
channel, broadcast control channel, paging control channel and common control channel
being logical channels for said synchronization data, system information, paging information
and forward access grant information characteristics, respectively.
8. A method for branching data in a mobile communication terminal, as set forth in Claim
1, wherein, in said data sending mode, said media access control sublayer of said
mobile station is adapted to, if said traffic characteristic information includes
random access data, short message data and no radio bearer-type short packet data
characteristics, attach types of a common control channel, dedicated control channel
and dedicated traffic channel to said media access control header contained in said
data to be sent and multiplex said common control channel, dedicated control channel
and dedicated traffic channel to a random access channel in a many-to-one manner to
branch said data to be sent, to the random access channel, said common control channel,
dedicated control channel and dedicated traffic channel being logical channels for
said random access data, short message data and no radio bearer-type short packet
data characteristics, respectively, said random access channel being a transport channel.
9. A method for branching data in a mobile communication terminal, as set forth in Claim
1, wherein, in said data sending mode, said media access control sublayer of said
mobile station is adapted to, if said traffic characteristic information includes
signaling data and radio bearer-type short/long packet data characteristics, attach
types of a dedicated control channel and dedicated traffic channel to said media access
control header contained in said data to be sent and multiplex said dedicated control
channel and dedicated traffic channel to a dedicated channel in a many-to-one manner
to branch said data to be sent, to the dedicated channel, said dedicated control channel
and dedicated traffic channel being logical channels for said signaling data and radio
bearer-type short/long packet data characteristics, respectively, said dedicated channel
being a transport channel.
10. A method for branching data in a mobile communication terminal, as set forth in Claim
1, wherein, in said data sending mode, said media access control sublayer of said
network is adapted to, if said traffic characteristic information includes forward
access grant information, short message data and no radio bearer-type short packet
data characteristics, attach types of a common control channel, dedicated control
channel and dedicated traffic channel to said media access control header contained
in said data to be sent and multiplex said common control channel, dedicated control
channel and dedicated traffic channel to a forward access channel in a many-to-one
manner to branch said data to be sent, to the forward access channel, said common
control channel, dedicated control channel and dedicated traffic channel being logical
channels for said forward access grant information, short message data and no radio
bearer-type short packet data characteristics, respectively, said forward access channel
being a transport channel.
11. A method for branching data in a mobile communication terminal, as set forth in Claim
1, wherein, in said data sending mode, said media access control sublayer of said
network is adapted to, if said traffic characteristic information includes multicast
signaling data and multicast data characteristics, attach types of a dedicated control
channel and dedicated traffic channel to said media access control header contained
in said data to be sent and multiplex said dedicated control channel and dedicated
traffic channel to a downlink shared channel in a many-to-one manner to branch said
data to be sent, to the downlink shared channel, said dedicated control channel and
dedicated traffic channel being logical channels for said multicast signaling data
and multicast data characteristics, respectively, said downlink shared channel being
a transport channel.
12. A method for branching data in a mobile communication terminal, as set forth in Claim
1, wherein, in said data sending mode, said media access control sublayer of said
network is adapted to, if said traffic characteristic information includes signaling
data and radio bearer-type short/long packet data characteristics, attach types of
a dedicated control channel and dedicated traffic channel to said media access control
header contained in said data to be sent and multiplex said dedicated control channel
and dedicated traffic channel to a dedicated channel in a many-to-one manner to branch
said data to be sent, to the dedicated channel, said dedicated control channel and
dedicated traffic channel being logical channels for said signaling data and radio
bearer-type short/long packet data characteristics, respectively, said dedicated channel
being a transport channel.
13. In a method for performing data communication between a mobile station and a network
which have media access control sublayers, respectively, a method for branching data
in a mobile communication terminal, comprising the steps of:
a) allowing each of said media access control sublayers of said mobile station and
network to set information regarding connection between logical channels and transport
channels on the basis of traffic characteristic information and a radio bearer status;
b) allowing each of said media access control sublayers to attach logical channel
types based on the set connection information to a media access control header contained
in data to be sent, in a data sending mode; and
c) allowing each of said media access control sublayers to branch said data to be
sent, to transport channels corresponding to the attached logical channel types.
14. A method for branching data in a mobile communication terminal, as set forth in Claim
13, further comprising the steps of:
d) allowing each of said media access control sublayers to determine logical channels
corresponding to logical channel types of a media access control header contained
in received data in a data receiving mode; and
e) allowing each of said media access control sublayers to branch said received data
to said determined logical channels.